Portable electric lamp



Aug. 27, 1929. P. RATHMANN I PORTABLE ELECTRIC LAMP Filed Dec. 29, 1927I Patented Aug. 27, 1929.

UNITED STATES; PATENT I OFFICE.

PAUL RATHMANN, OF BODEIQ'BACH, CZECI'IOSLOVAKIA, ASEIGNOR. TOELEKTROTEGH- NISCHE FABRIK SGHIVQIDT 82; 00., GESELLSCHAFT'MLB- 11, OFBODENBACH, CZECHO- SLOVAKIA.

PORTABLE ELECTRIC LAMP.

Application filed December 29, 1927, Serial No. 243,321, and inCzechoslovakia April 21,, 1927.

My invention relates to portable electric lamps such as flash lights,hand lamps and the like. It is an object of my invention to provide morereliable means for facilitating the insertion of the battery in suchlamps.

The portable lamps hitherto in use involve the drawback that theinsertion of the battery requires great care as the battery must beinserted in a definite position so that its contact springs will engagethe two contacts of the casing. It is not easy to insert the batteryproperly in the dark to make the lamp operate immediately. An-

other weak point of the lamps hitherto used is the switch which oftenfails and renders the lamp inoperable.

Both these drawbacks are overcome according to this invention byduplicating one of the two contacts in the casing, so that the batterymay be inserted in any position with respect to the duplicate contact,and by providing a switching lever which is electrically connected withthe casing and with one pole of the lamp and cooperates with a contactspring forming the other pole of the lamp and insulated from the casing.The contact spring locks the switching lever in two positions but makescontact with it only in one position, insulating means being providedfor breaking the electrical connection in the other position. Preferablysuchinsulating means are secured to the switching lever.

My invention simplifies the design of casings for lamps of the kinddescribed to such an extent that they can be manufactured at very lowcost and on a quantity production basis.

In the drawings affixed to this specification and forming part thereof,a flash light equipped with my improvements is illustrateddiagrammatically by way of example.

In the drawings Fig. 1 is a rear end elevation of the lamp partly brokenopen,

Fig. 2 is a central vertical section of the lamp,

Fig. 3 is a part sectional elevation showin the switching lever and itsaccessories t: on a larger scale.

Referring now to the drawings, and first to Figs. 1 and 2, 1 is theduplicate contact piece or bridge, being a fiat body of sheet metal orthe like, with two flanges 2 each constituting a contact for the contactspring of the battery. The flanges 2, 2 are attached to the side walls 3of the casing but insulated from them by insulating strips 4 and 7Tongues or other means 5 are provided at the contact piece for securingit in the case0 ing, such tongues being inserted in slots of the innerinsulating strip 4, bent over so as to hub the strip, and held out ofcontact with the walls 3 by the outer strip 7.

6 is a threaded socket for inserting an in- 5 candescent lamp, notshown, so that the lamp will make contact with the body of the bridge 1intermediate its flanges 2, 2.

It will be understood that when a battery, not shown, is insertedbetween the flanges 2, 2 of the part 1 it does not matter in whichposition it is with respect to the flanges, as its contact spring willengage one of the flanges 2, 2 in any position. The other contact springof the battery will be engaged by the spring 9.

' Referring now to Fig. 3, 8 is a switching lever which is pivoted inthe casing at 10 and electrically connected with the second pole of theincandescent lamp, 9 is a contact spring secured to, but insulated fromthe easing by the insulating strips 4, 7, and 11 is a strip ofinsulating material at one side of the V-shaped base of the switchinglever 8. The other side is not insulated.

In operation and in the position illustrated in Fig. 3, the plain sideof the V-shaped end of lever 8 makes contact with the spring 9 and isheld in position by the reaction of the spring, contact being nowestablished between the lamp and the battery. By throwing over the leverinto its opposite position, as shown in Fig. 2, the insulatingstrip 11on the other side of the V is brought into engagement with the spring 9so that the lamp circuit is broken.

Instead of securing the insulating strip 11 at the switching lever itmight be provided at the spring 9 so as to be engaged by the lever 8only in one of its positions.

I wish it to be understood that I do not de sire to be limited except bythe scopeof the claim to the exact details of construction shown anddescribed for obvious modifications will occur to a person skilled inthe art.

I claim A portable electric lamp comprising a casing, a contact bridgehaving a flange secured to and insulated from each side wall of saidcasing and adapted to be engaged by a contact of a battery in saidcasing, a lamp socket in said casing facing said bridge intermediate itsflanges, a contact spring, a switching lever adapted to cooperate withsaid contact spring and to be held in two positions by the reaction ofsaid spring, and an insulating strip adapted to be lnterposed betweensaid contact and 10 said spring in one of the positions of said lever.

In testimony whereof I afiix my signature.

PAUL RATHMANN.

